It is known to use a two-piece closure member that includes an armature connected to a needle, and to allow fuel flow through the known closure member. In particular, these known closure members are believed to have angled holes drilled through the armature such that fuel flow through the known closure member must make two turns or bends, i.e., at the entrance and exit of the angled holes. It is believed that the circuitous fuel flow path caused by these turns or bends, combined with the heavy armature of the known closure members, slows the movement, and hence response time, of these known closure members.
In order to increase closure member speed and improve fuel injector performance, it is believed that there is a need to eliminate the turns or bends in the fuel flow path and to reduce the weight of known closure members